A key area in which there needs to be a review of the role of marketing communications is social marketing, a concept that has existed since the early 1970s but which has received renewed focus internationally in the last few years. A re-examination of the role and effectiveness of advertising as a marketing communications tool began in the late 1980s, and accelerated through the early 1990s. Unsurprisingly, a greater emphasis on determining the return on investment from marketing activity also occurred, leading to a focus on the measurement of the impact of marketing communications activity which continues in the current era. Marketing communications can be considered to have a positive effect on brand equity / valuation if the brand's value and the changes in that value over time are measurable and if marketing communications can be shown to be a major contributor to that change.